[fpc-devel] type question

[Marc Weustink]

Peter Vreman wrote:
>> On Saturday 14 October 2006 15:55, Marc Weustink wrote:
>>> Hi,
>>>
>>> if I define 2 types like:
>>>
>>> type
>>>   MyA = type string;
>>>   MyB = type string;
>>>
>>> are MyA and MyB considered as the same type ?
>> No, you are explicitly marking them as a new type. This is a very cool
>> feature
>> of Pascal you wont find in many other languages.
>>
>> (For instance, you could use it to create a new integer-type for little-
>> and
>> big-endian numbers, ensuring that you _never_ directly assign a
>> little-endian
>> number to a big-endian one, or vice versa)
> 
> For the compiler the types are not equal anymore, but they are still
> compatible for implicit type conversion. This has mainly impact on
> overload choosing and parameter passing. Normal assignments using ':=' are
> not affected because of the still available implicit type conversion.

I came to this when I wanted to do operator overloading on them. The
compiler complained that you cannot overload for equal types.

So I wanted first to know if it are equal types or not.

Next question: Should operator overloading be possible on such types ?

Marc